check engine CADILLAC ATS COUPE 2015 1.G Owner's Guide

Black plate (17,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
Vehicle Care 10-17
{Warning
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
{Caution
Using coolant other than
DEX-COOL®can cause
premature engine, heater core,
or radiator corrosion. In addition,
the engine coolant could require
changing sooner. Any repairs
would not be covered by the
(Continued)
Caution (Continued)
vehicle warranty. Always use
DEX-COOL (silicate-free) coolant
in the vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant. SeeMaintenance Schedule
on page 11-3 andRecommended
Fluids and Lubricants on
page 11-13.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating on
page 10-20.
What to Use
{Warning
Adding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or others
could be burned. Use a 50/
50 mixture of clean, drinkable
water and DEX-COOL coolant.
Use a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant. This mixture:
.Gives freezing protection down
to −37°C (−34°F), outside
temperature.

Black plate (18,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-18 Vehicle Care
.Gives boiling protection up to
129°C (265°F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
{Caution
If improper coolant mixture,
inhibitors, or additives are used in
the vehicle cooling system, the
engine could overheat and be
damaged. Too much water in the
mixture can freeze and crack
engine cooling parts. The repairs
would not be covered by the
vehicle warranty. Use only the
proper mixture of engine coolant
for the cooling system. See
Recommended Fluids and
Lubricants on page 11-13.Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and your
health.
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
It is normal to see coolant moving in
the upper coolant hose return line
when the engine is running. It is
also normal to see bubbles entering
the surge tank through the
small hose.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. If coolant is visible but the coolant
level is not at or above the COLD
FILL line, add a 50/50 mixture of
clean drinkable water and
DEX-COOL coolant.
Be sure the cooling system is cool
before this is done.
If no coolant is visible in the coolant
surge tank, add coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Caution
This vehicle has a specific
coolant fill procedure. Failure to
follow this procedure could cause
the engine to overheat and be
severely damaged.
If no problem is found, check to see
if coolant is visible in the coolant
surge tank. If coolant is visible but
the coolant level is not at the bottom
of the fill neck, add a 50/50 mixture
of clean, drinkable water and

Black plate (20,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-20 Vehicle Care
1. Remove the coolant surge tankpressure cap from the top
chamber when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise. If you hear a
hiss, wait for that to stop. This
will allow any pressure still left to
be vented out the
discharge hose.
2. Keep turning the pressure cap slowly and remove it. Open the
surge tank service port cap to
the lower chamber
3. Fill the surge tank top chamber with the proper DEX-COOL
coolant mixture to the bottom of
the fill neck. The top chamber
needs to be completely full. Fill
the surge tank bottom chamber
through the service port to
approximately half. 4. With the coolant surge tank
pressure cap off and the surge
tank service port cap open, start
the engine and let it run until you
can feel the upper radiator hose
getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level
inside the coolant surge tank top
chamber may be lower. If the
level is lower, add more of the
proper DEX-COOL coolant
mixture to the surge tank top
chamber until the level reaches
the bottom of the fill neck.
5. Replace the surge tank pressure cap tightly and close the surge
tank service port cap.
{Caution
If the pressure cap is not tightly
installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured. Check the level in the surge tank
top and bottom chambers when the
cooling system has cooled down.
If the coolant is not at the proper
levels, repeat Steps 1–3 and
reinstall the pressure cap and close
the service port. If the coolant still is
not at the proper levels when the
system cools down again, see your
dealer.
Engine Overheating
The vehicle has several indicators
to warn of the engine overheating.
There is an engine coolant
temperature gauge and an engine
coolant temperature warning light on
the instrument cluster See
Engine
Coolant Temperature Gauge on
page 5-13 andEngine Coolant
Temperature Warning Light on
page 5-22. The vehicle may also
display a message on the Driver
Information Center (DIC). See
Engine Cooling System Messages
on page 5-34.

Black plate (21,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
Vehicle Care 10-21
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Service on page 13-5.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fan is running. If the engine
is overheating, the fan should be
running. If it is not, do not continue
to run the engine. Have the vehicle
serviced.
{Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
If Steam Is Coming from the
Engine Compartment
{Warning
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Just turn it
off and get everyone away from
the vehicle until it cools down.
Wait until there is no sign of
steam or coolant before you open
the hood.
If you keep driving when the
engine is overheated, the liquids
in it can catch fire. You or others
could be badly burned. Stop the
engine if it overheats, and get out
of the vehicle until the engine
is cool.
If No Steam Is Coming from
the Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral) for an automatic
transmission or Neutral for a
manual transmission, and let the
engine idle.

Black plate (22,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-22 Vehicle Care
If the engine coolant temperature
gauge is no longer in the
overheated area or the engine
coolant temperature warning light no
longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe vehicle distance from the
vehicle in front. If the warning does
not come back on, continue to drive
normally and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle the
engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an
area where the temperature may fall
below freezing, use a fluid that has
sufficient protection against
freezing.
Adding Washer Fluid
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. SeeEngine
Compartment Overview on
page 10-5 for reservoir location.
{Caution
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
.Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
.When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
.Fill the washer fluid tank only
three-quarters full when it is
very cold. This allows for fluid
expansion if freezing occurs,
which could damage the tank
if it is completely full.

Black plate (24,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-24 Vehicle Care
There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake/clutch
hydraulic system can also cause
a low fluid level. Have the brake/
clutch hydraulic system fixed,
since a leak means that sooner
or later the brakes will not
work well.
Do not top off the brake/clutch fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove fluid, as
necessary, only when work is done
on the brake/clutch hydraulic
system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake/clutch
hydraulic system.
Checking Brake Fluid
The brake/clutch fluid can be
checked without taking off the cap
by looking at the brake/clutch fluid
reservoir.
The fluid level should be above
MIN. If it is not, have the brake/
clutch hydraulic system checked to
see if there is a leak.
After work is done on the brake/
clutch hydraulic system, make sure
the level is above MIN but not over
the MAX mark. When the brake/clutch fluid falls to a
low level, the brake warning light
comes on. See
Brake System
Warning Light on page 5-18.
What to Add
Use only new GM approved DOT 3
brake fluid from a sealed container.
See Recommended Fluids and
Lubricants on page 11-13.
Always clean the brake/clutch fluid
reservoir cap and the area around
the cap before removing it. This
helps keep dirt from entering the
reservoir.
{Warning
With the wrong kind of fluid in the
brake/clutch hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake/clutch fluid.

Black plate (27,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
Vehicle Care 10-27
1. Before starting this check, besure there is enough room
around the vehicle.
2. Apply both the parking brake and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. For automatic transmission vehicles, try to start the engine
in each gear. The vehicle should
start only in P (Park) or
N (Neutral). If the vehicle starts
in any other position, contact
your dealer for service.
For manual transmission
vehicles, put the shift lever in
Neutral, push the clutch pedal
down halfway, and try to start
the engine. The vehicle should
start only when the clutch pedal
is pushed down all the way to
the floor. If the vehicle starts
when the clutch pedal is not
pushed all the way down,
contact your dealer for service.Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake
immediately if the vehicle begins
to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot

Black plate (28,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-28 Vehicle Care
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear and cracking.
See Maintenance Schedule on
page 11-3.
Replacement blades come in
different types and are removed in
different ways. For proper type and
length, see Maintenance
Replacement Parts on page 11-15. To replace the windshield wiper
blade:
1. Pull the windshield wiper
assembly away from the
windshield.
2. Lift up on the latch in the middleof the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm. 4. Remove the wiper blade.
Allowing the wiper blade arm to
touch the windshield when no
wiper blade is installed could
damage the windshield. Any
damage that occurs would not
be covered by the vehicle
warranty. Do not allow the wiper
blade arm to touch the
windshield.
5. Reverse Steps 1–3 for wiper blade replacement.
Windshield Replacement
The windshield is part of the HUD
system. If the vehicle has to have
the windshield replaced, get one
that is designed for HUD or the
HUD image may look out of focus.

Black plate (32,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-32 Vehicle Care
Fuses and Circuit
Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
breakers. This greatly reduces the
chance of damage caused by
electrical problems.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace
a bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can
be temporarily borrowed from
another fuse location, if a fuse goes
out. Replace the fuse as soon as
possible.
To identify and check fuses, circuit
breakers, and relays, seeEngine
Compartment Fuse Block on
page 10-32, Instrument Panel Fuse
Block on page 10-35, and Rear
Compartment Fuse Block on
page 10-38.
Engine Compartment
Fuse Block
The underhood fuse block is on the
passenger side of the engine
compartment.
Lift the fuse block cover to access
the fuses.
The vehicle may not be equipped
with all of the fuses and relays
shown.
{Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the
covers on any electrical
component.

Black plate (40,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707477) - 2015 - crc - 9/15/14
10-40 Vehicle Care
Number Usage42 Memory Seat Module
43 Body Control Module 3
44 Not Used
45 Battery Regulated Voltage Control
46 Engine Control Module Battery
47 Not Used
48 Not Used
49 Trailer ModuleWheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much flexing.
There could be a blowout
(Continued)
Warning (Continued)
and a serious crash. See
Vehicle Load Limits on
page 9-11.
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are more
likely to be cut, punctured,
or broken by a sudden
impact —such as when
hitting a pothole. Keep
tires at the recommended
pressure.
(Continued)